Android学习历程-上下文菜单(Context Menu)

不知道怎样调用上下文菜单，探索中....

package com.example.testcontextmenu;


import android.os.Bundle;
import android.app.Activity;
import android.graphics.Color;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;

public class MainActivity extends Activity {

	private TextView myTextView = null;
	
	private static final int TIME1=Menu.FIRST;
	
	private static final int TIME2=Menu.FIRST+1;
	
	private static final int TIME3=Menu.FIRST+2;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		myTextView = (TextView)findViewById(R.id.myTextView);
		//注册上下文菜单
		registerForContextMenu(myTextView);
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.activity_main, menu);
		return true;
	}

	@Override
	public boolean onContextItemSelected(MenuItem item) {
		switch (item.getItemId()) {
		case TIME1:
			myTextView.setBackgroundColor(Color.RED);
			break;
		case TIME2:
			myTextView.setBackgroundColor(Color.GREEN);
			break;
		case TIME3:
			myTextView.setBackgroundColor(Color.WHITE);
			break;
		}
		return true;
	}

	@Override
	public void onCreateContextMenu(ContextMenu menu, View v,
			ContextMenuInfo menuInfo) {
		menu.add(0, TIME1, 0, "红色背景");
		menu.add(0, TIME2, 0, "绿色背景");
		menu.add(0, TIME3, 0, "白色背景");
	}

	
}

　　

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/myTextView"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:text="@string/hello_world" />

</RelativeLayout>